Design, Fabrication and Testing of Micro- Nanoscale Thin-Film Resistance Temperature Detectors
Abstract
The development of the microelectronics industry has triggered a broad scientificrevolution. The ever ongoing quest for miniaturization and the thermal challengesthat follow have made heat transfer in confined spaces one of the most researchedtopics in recent time. The increasingly compact devices encountered in everydaylife have motivated the need for new and efficient cooling techniques for the re-moval of the high heat duties produced by these systems. The two-phase flowboiling microchannel heat sink is recognized as one of the top candidates for sucha task, with its promise of high heat removal capabilities through its latent heatof evaporation and favorable pressure drop with respect to its single-phase coun-terpart. However, the research is still in its infancy stage, requiring knowledgeand insight in the fundamental mechanisms involved, as the conventional continu-ity assumptions valid in the macro-world may not be applicable on these smallerscales, as the contradicting results of previous studies indicate. The main causes ofthese dispersions are believed to be related to the intrusive nature of the metrologydevices used in the research, which disturbe the flow field and yield false values.The research community is in high demand of benchmark data on localized mea-surements regarding both temperature and heat-flux. In this work, novel platinumthin-film resistance temperature detectors with high sensitivity are produced tomeet this high demand. Four size variations of the sensors are successfully ob-tained, i.e. 3 µm 2 , 4µm 2 , 5µm 2 , and 6µm 2 , with corresponding wire tracks of 60nm, 80nm, 100nm, and 120nm, respectively, and a thin-film thickness of 40 nm.Measurements show that the mean sheet resistances of these sensors exceed thatof previous results found in the literature by approximately 200 Ω at a size severalorders of magnitude lower. To the author s knowledge, the RTD s produced in thiswork are the smallest ever made.